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Thermodynamics and Intermolecular Interactions of Nicotinamide in Neat and Binary Solutions: Experimental Measurements and COSMO-RS Concentration Dependent Reactions Investigations
PublikacjaIn this study, the temperature-dependent solubility of nicotinamide (niacin) was measured in six neat solvents and five aqueous-organic binary mixtures (methanol, 1,4-dioxane, acetonitrile, DMSO and DMF). It was discovered that the selected set of organic solvents offer all sorts of solvent effects, including co-solvent, synergistic, and anti-solvent features, enabling flexible tuning of niacin solubility. In addition, differential...
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Study of oxygen electrode reactions on symmetrical porous SrTi0.30Fe0.70O3-δ electrodes on Ce0.8Gd0.2O1.9 electrolyte at 800 °C–500 °C
PublikacjaIron doped strontium titanates (SrTi1-xFexO3-δ) are an interesting mixed ionic-electronic conductor model used to study basic oxygen reduction/oxidation reactions. In this work, we performed an impedance spectroscopy study on symmetrical porous SrTi0.30Fe0.70O3-δ (STF70) electrodes on a ceriabased electrolyte. The sample was measured in varying oxygen concentration: from 0.3% to 100% in 800 °C - 500 °C temperature range. Low polarisation...
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Multisine impedimetric probing of biocatalytic reactions for label-free detection of DEFB1 gene: How to verify that your dog is not human?
PublikacjaAlbert is a dog (Canis familiaris), but he does not realize this. Albert loves human food (and beer), watching movies on the internet, sleeping in bed, and more. But he should not do all these things. To convince him that, we have desinged a test procedure. The DEFB1 gene is unique to human species. Detecting its presence from saliva and in short periods may offer an advantage in the field of forensic medicine, and influence Albert’s...
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A New Three-Dimensional Space Vector Modulation for Multilevel Four-Leg Converters Based on the Shape Functions of Tetrahedral Element
PublikacjaThe paper proposes a new three-dimensional space vector pulse-width modulation (3D-SVPWM) algorithm for multilevel four-leg converters. The proposed PWM duty cycle calculation is based on the shape functions of the threedimensional tetrahedral finite elements. The algorithm ensures synthesis of accurate and undistorted output voltages even under significant imbalance or ripple in the DC-link voltages. At the same time, the algorithm...
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Advanced oxidation processes (AOPs) based wastewater treatment - unexpected nitration side reactions - a serious environmental issue: A review
PublikacjaChemical compounds containing nitro group (nitro-products) are a one of toxic by-products, that can be formed during wastewater treatment processes. In case of presence of nitrite or nitrate ions, the formation of nitro-products during advanced oxidation processes (AOPs) is very common. It is caused by the reactive nitrogen species (RNs) such as nitrate radical (NO3•), nitrite radical (NO2•), nitrogen oxide radical (NO•) and peroxynirite...
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NPC assessment in insulated DC/DC converter topologies using SiC MOSFETs for Power Electronic Traction Transformer
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Improved model of isothermal and incompressible fluid flow in pipelines versus the Darcy–Weisbach equation and the issue of friction factor
PublikacjaIn this article, we consider the modelling of stationary incompressible and isothermal one-dimensional fluid flow through a long pipeline. The approximation of the average pressure in the developed model by the arithmetic mean of inlet and outlet pressures leads to the known empirical Darcy–Weisbach equation. Most importantly, we also present another improved approach that is more accurate because the average pressure is estimated...
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The Impact Of The Selected Parameters Of Fdm Manufacturing Technology On Tribological Performance Of Abs–Steel Pair Under Dry Friction
PublikacjaThe paper presents the result of tribological test of ABS and steel samples sliding under dry friction. Polymeric samples were manufactured of ABS material using FDM technology. Testing was carried out in unidirectional sliding in a ring-on-flat contact in a PT-3 tribometer. The scope of tested parameters included volumetric and mass wear, the friction coefficient, and polymeric specimen temperature. Polymeric specimens used in...
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Tribo-Environment Dependent Chemical Modification of Sliding Interfaces in Ultrananocrystalline Diamond Nanowall Film: A Correlation with Friction and Wear
PublikacjaTribological properties of ultrananocrystalline diamond nanowall (UNCD NW) films were investigated quantitatively in three different and controlled tribo-environmental conditions, proposing the passivation and graphitization mechanisms. However, these mechanisms are rather complicated and possibly can be understood in well-controlled tribological conditions. It was shown that the friction and wear of these films were high in highPage 1...
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Influence of the Tool Rotational Speed on Physical and Chemical Properties of Dissimilar Friction-Stir-Welded AA5083/AA6060 Joints
PublikacjaAluminum alloys have been successfully used in the railroad and automotive industries because of their potential to significantly reduce component weights, and their good mechanical and anti-corrosion properties. Problems with joining aluminum alloys are characterized by low weldability, which influences the need for studies focused on unconventional methods. The environmentally friendly and low-cost friction-stir-welding method...
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Airborne wear particle emission from train brake friction materials with different contents of steel and copper fibres
PublikacjaThis study investigated the influence of the amount of steel and copper fibres in a train brake friction material on the tribological performance, emission intensity and characteristics of airborne wear particles. The particles were generated on a pin-on-disc tribometer under controlled friction and environmental conditions. It was found that the steel fibre results in a more intensive emission of 0.3–10 μm particles compared to...
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Induction Assisted Hybrid Friction Stir Welding of Dissimilar Materials AA5052 Aluminium Alloy and X12Cr13 Stainless Steel
PublikacjaThis research aimed to study the induction in-situ heated hybrid friction stir welding (IAFSW) method to join AA5052 aluminium alloy with X12Cr13 stainless steel (SS) to enhance joint strength. The potency of this method on the mechanical properties and microstructural characterizations were also investigated. The results show that the transverse tensile strength gained was 94% of the AA5052 base metal that is 229.5 MPa. This superior...
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Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublikacjaThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
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Analytical solution of non-stationary heat conduction problem for two sliding layers with time-dependent friction conditions
PublikacjaIn this article we conduct an overview of various types of thermal contact conditions at the sliding interface. We formulate a problem of non-stationary heat conduction in two sliding layers with generalized thermal contact conditions allowing for dependence of the heat-generation coefficient and contact heat transfer coefficient on time. We then derive an analytical solution of the problem by constructing a special coordinate...
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Effect of Tool Positioning Factors on the Strength of Dissimilar Friction Stir Welded Joints of AA7075-T6 and AA6061-T6
PublikacjaFriction Stir Welding (FSW) is a solid-state bonding technique. There are many direct and indirect factors affecting the mechanical and microstructural properties of the FSW joints. Tool offset, tilt angle, and plunge depth are determinative tool positioning in the FSW process. Investigating the effect of these factors simultaneously with other parameters such as process speeds (rotational speed and translational speed) and tool...
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Some Aspects of Shear Behavior of Soft Soil–Concrete Interfaces and Its Consequences in Pile Shaft Friction Modeling
PublikacjaThis paper examines the stiffness degradation and interface failure load on soft soil–concrete interface. The friction behavior and its variability is investigated. The direct shear tests under constant normal load were used to establish parameters to hyperbolic interface model which provided a good approximation of the data from instrumented piles. Four instrumented piles were used to obtain reference soil–concrete interface behavior....
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Transition dipole moment functions of the KRb molecule
Dane BadawczeElectronic transition dipole moment functions (TDMF) have been calculated for the singlet (s) and triplet (t) Sigma+ (S+), Pi (P), and Delta (D) electronic states of the KRb molecule. TDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. All results of the transition dipole moments...
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Permanent dipole moment functions of the KRb molecule
Dane BadawczeElectronic permanent dipole moment functions (PDMF) have been calculated for the singlet (s) and triplet (t) Sigma+, Sigma-, Pi, and Delta electronic states of the KRb molecule. PDMFs are needed in understanding processes like photodissociation, photoassociation, cooling, and trapping of molecules. All results of the permanent dipole moments have been...
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Identification of lipid fraction constituents from grasshopper (Chorthippus spp.) abdominal secretion with potential activity in wound healing with the use of GC–MS/MS technique
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Obtaining of Coumarone-Indene Resins Based on Light Fraction of Coal Tar. 4. Bitumen-Polymer Blends with Participation of Coumarone-Indene Resins with Epoxy Groups
PublikacjaUsing light fraction of coal tar (5.75 wt % of coumarone and 44.45 wt % of indene), glycidyl methacrylate and styrene, the coumarone-indene resin with epoxy groups (CIRE) has been synthesized. Monoperoxy derivative of diglycidyl ether Bisphenol A (PO) was used as an initiator. The possible formation of CIRE has been studied on the model systems consisting of PO, glycidyl methacrylate, indene or coumarone, or styrene, or mixture...
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UV-Vis-Induced Degradation of Phenol over Magnetic Photocatalysts Modified with Pt, Pd, Cu and Au Nanoparticles
PublikacjaThe combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhances the separation and recoverable properties of nanosized TiO2 photocatalyst. Metal-modified (Me = Pd, Au, Pt, Cu) TiO2/SiO2@Fe3O4 nanocomposites were prepared by an ultrasonic-assisted sol-gel method. All prepared samples were characterized by X-ray powder diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy...
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Antibiotic usage at a clinical paediatric hospital before and after the implementation of actions related to the hospital antibiotic policy
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Towards a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Toward a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Principles for the Application of Vibration Intensity Scale for the Prediction and Assessment of Impact of Actions of Exploitation Mine on Buildings and People
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Exploring the Institutional and Bottom-Up Actions for Urban Air Quality Improvement: Case Studies in Antwerp and Gdańsk
PublikacjaThe article presents the results of qualitative studies concerning the presence of air quality management in the process of urban planning and in the public discourse in Antwerp, Belgium, and Gdańsk, Poland. We focused on the way urban planners, environmental experts, and stakeholders perceive the problem of air pollution, especially with respect to urban development policy, and whether they consider it one of the major factors...
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Speciation of heavy metals in bottom sediments of drinking water reservoir for Gdansk, Poland – changes over the 14 years
PublikacjaThere was conducted a comparative study of the concentrations of heavy metals (Zn, Cu, Pb, and Cd) in the surface layer of sediments collected in two investigation periods: 1999–2000 and 2013. Theresults demonstrated that the degree of metals pollution decreased over time. The contamina-tion factors (Cf) calculated for Zn, Cu, Pb, and Cd were respectively 3.63, 3.86, 3.23, and 3.25 in the first period of research and 1.35, 3.42,...
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In silico study on the effects of carbonyl groups on chemical equilibrium of reactions with a polar product occurring under confinement in pores of activated carbons
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Relationships between acute reactions to radiotherapy in head and neck cancer patients and parameters of radiation-induced DNA damage and repair in their lymphocytes
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The Effectiveness of Computerized Cognitive Training Combined With Whole Body Cryotherapy in Improving Cognitive Functions in Older Adults. A Case Control Study
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Copper and copper-manganese 1D coordination polymers: Synthesis optimization, crystal structure and preliminary studies as catalysts for Baylis–Hillman reactions
PublikacjaThis work reports the influence of experimental parameters (pH and counter-ion) in the synthesis of the 1D coordination polymer [Cu(IDA)(H2O)2]n (IDA = iminodiacetate), named here Cu-IDA. Copper-manganese bimetallic coordination polymers were also obtained by isomorphic replacement into Cu-IDA structure, with different molar ratio of Cu2+ and Mn2+ ions, denoted here as Cu/Mn-IDA (0.9/0.1; 0.7/0.3 and 0.5/0.5). New coordination...
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Development of Physics-Based Energy Functions that Predict Medium-Resolution Structures for Proteins of the α, β, and α/β Structural Classes
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A Dirac delta-type orthogonality relation for the on-the-cut generalized associated Legendre functions of the first kind with imaginary second upper indices
PublikacjaThe orthogonality relation for the on-the-cut generalized associated Legendre functions of the first kind with imaginary second upper indices is evaluated in a closed form. It is found to be proportional to a sum of two terms, both depending on the second upper indices and containing the Dirac delta distribution.
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Virtual Space Vector Pulse Width Modulation Algorithm for Three-Level NPC Converters Based on the Final Element Shape Functions
PublikacjaThe paper puts forth a novel idea for the computation of Nearest Three Virtual Space Vector Pulse Width Modulation for the three level NPC converters. The computations are based on the concept of final element shape function widely used in the domain of finite element analysis. The proposed approach significantly frees the computations from the use of trigonometric functions, which simplifies the computations and permits easier...
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Recurrent Neural Network Based Adaptive Variable-Order Fractional PID Controller for Small Modular Reactor Thermal Power Control
PublikacjaThis paper presents the synthesis of an adaptive PID type controller in which the variable-order fractional operators are used. Due to the implementation difficulties of fractional order operators, both with a fixed and variable order, on digital control platforms caused by the requirement of infinite memory resources, the fractional operators that are part of the discussed controller were approximated by recurrent neural networks...
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Application of gas chromatography to the study of the kinetics of reactionsin solution. Ring opening reactions for á-lactams studied using internal standard
PublikacjaW pracy przedstawiono metodę badania kinetyki reakcji otwarcia pierścienia á-laktamu, wykorzystującą technikę chromatografii gazowej. Na podstawie badań kinetyki reakcji w różnych temperaturach wyznaczono wartości energii aktywacji dwóch badanych reakcji. Podstawowym celem pracy było pokazanie możliwości wykorzystania GC w badaniach kinetyki reakcji prowadzonych w mikroskali.
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Lower rim substituted tert-butylcalix[4]arenes.Part 8: Calix[4]arenes with dialkoxyphosphoryl functions. Synthesis and complexing properties
PublikacjaW pracy przedstawiono syntezę i charakterystykę otrzymanych związków (1, 2), pochodnych alkoksyfosforylowych p-tert-butylokaliks[4]arenu: 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-diizopropoksyfosforylopropoksy)kaliks[4]arenu (1) oraz 5,11,17,23-tetra-tert-butylo-25,26,27,28-tetrakis(3-methoksyetoksyfosforylopropoksy)kaliks[4]arenu (2). Zbadano właściwości jonoforowe związków 1 i 2 w membranie elektrod jonoselektywnych,...
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Friction and wear behaviour of self mated DLC and DLC-W coatings in water or salt in water solution lubricated sliding
PublikacjaPrzedstawiono wyniki badań powłok ceramicznych DLC oraz DLC z wolframem (DLC-W) nałożonych na podłoże ze stali nierdzewnej,przy tarciu ślizgowym , w modelowym skojarzeniu o styku konforemnym (płaskie czoło obracającej się względem swojej osi tulei - powierzchnia płaska). Badania prowadzono stosując smarowanie wodą destylowaną albo wodnym roztworem soli - NaCl. Wyznaczano współczynniki tarcia oraz intensywność zużywania ceramicznej...
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Dynamic Properties of Two-Axle Freight Wagon with UIC Double-Link Suspension as a Non-smooth System with Dry Friction
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Review on friction stir welding of dissimilar magnesium and aluminum alloys: Scientometric analysis and strategies for achieving high-quality joints
PublikacjaMagnesium and aluminum alloys continually attract interest as lightweight structural materials for transport applications. However, joining these dissimilar alloys is very challenging. The main obstacle that hinders progress in dissimilar Mg-Al joining is the formation of brittle intermetallic compounds (IMCs). As a solid-state joining technique, FSW is an excellent candidate to attenuate the deleterious IMC effects in dissimilar...
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Investigation on polypropylene friction stir joint: effects of tool tilt angle on heat flux, material flow and defect formation
PublikacjaTool tilt angle (TTA) is a critical factor that can control material flow in polymeric materials' friction stir joining (FSJ). This study selected a TTA range between 0° to 4° for FSJ of polypropylene (PP) polymer sheet. A modified computational fluid dynamic (CFD) technique was implemented to gain a deep understanding of the effects of TTA during FSJ of PP. The PP joint's internal flow, defect formation, heat generation, and tensile...
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Porosity and shape of airborne wear microparticles generated by sliding contact between a low-metallic friction material and a cast iron
PublikacjaThe wear of brakes in transport vehicles is one of the main anthropogenic sources of airborne particulate matter in urban environments. The present study deals with the characterisation of airborne wear microparticles from a low-metallic friction material / cast iron pair used in car brakes. Particles were generated by a pin-on-disc machine in a sealed chamber at sliding velocity of 1.3 m/s and contact pressure of 1.5 MPa. They...
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The Influence of Tool Shape and Process Parameters on the Mechanical Properties of AW-3004 Aluminium Alloy Friction Stir Welded Joints
PublikacjaThe purpose of the following study was to compare the effect of the shape of a tool onthe joint and to obtain the values of Friction Stir Welding (FSW) parameters that provide the bestpossible joint quality. The material used was an aluminium alloy, EN AW-3004 (AlMn1Mg1). To theauthors’ best knowledge, no investigations of this alloy during FSW have been presented earlier. Fivebutt joints were made with a self-developed, cylindrical,...
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Temperature Evolution, Material Flow, and Resulting Mechanical Properties as a Function of Tool Geometry during Friction Stir Welding of AA6082
PublikacjaThe friction stir welding process was simulated for joining AA6082 aluminum alloy with the use of the computational fluid dynamics method. Two different tool geometries were used—a tapered cylindrical pin (simple pin) and a hexagonal pin with grooves (complex pin). The analysis of the simulations performed was discussed in terms of temperature evolution during the process, total heat input, residual stresses and material flow....
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Determination of volatile aliphatic amines in air by solid phase microex traction coupled with gas chromatography with flame ionization detection.
PublikacjaOpisano nową metodę oznaczania lotnych amin alifatycznych w powietrzu. Metodyka oparta jest na zastosowaniu techniki mikroekstrakcji do fazy stacjonarnej na etapie pobierania próbek oraz zestawu GC-FID do rozdzielania i oznaczania poszczególnych analitów.Badaniom poddano nowe typy faz stacjonarnych.Zbadano wpływ wilgotności powietrza na proces pobierania próbek analitów z powietrza.
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Friction and flow around growing tissue in bioreactor. Proceedings of the Biomechanics 2003. Engineering Biomechanics - Biomechanics of Sport - Medical Biomechanics.
PublikacjaPrzedstawione zostały problemy teoretyczne związane z wyznaczaniem sił tarcia, współczynników tarcia, rozkładów wartości ciśnienia w warstwie przyściennej wytworzonej wokół hodowanej tkanki w bioreaktorze w trakcie opływu tej tkanki cieczami biologicznymi o właściwościach lepkosprężystych. Model Rivlina Ericksena lepkosprężystej cieczy biologicznej jest tu brany pod uwagę.
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The PARAGON Heart Failure trial – ongoing investigation of the angiotensin receptor antagonist/neprilysin inhibitor sacubitril/valsartan in heart failure patients with hypertension and preserved ejection fraction
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Speciation of heavy metals in bottom sediments of a drinking water reservoir for Gdańsk, Poland – changes over the 14 years
PublikacjaThere was conducted a comparative study of the concentrations of heavy metals (Zn, Cu, Pb, andCd) in the surface layer of sediments collected in two investigation periods: 1999–2000 and 2013.The results demonstrated that the degree of metals pollution decreased over time. The contaminationfactors (Cf) calculated for Zn, Cu, Pb, and Cd were respectively 3.63, 3.86, 3.23, and 3.25 in thefirst period of...
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Non-stoichiometric magnetite as catalyst for the photocatalytic degradation of phenol and 2,6-dibromo-4-methylphenol – a new approach in water treatment
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Immobilization of TiO2 and Fe–C–TiO2 photocatalysts on the cotton material for application in a flow photocatalytic reactor for decomposition of phenol in water
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